The present invention relates generally to disposable syringes and in particular to a shielding assembly for preventing accidental needle pricks.
The spread of Acquired Immune Deficiency Syndrome or AIDS in the 1980's, has greatly increased the concerns of health care providers over the spread of communicable diseases through accidental needle pricks. Nurses, doctors and other health care providers accidentally prick themselves with needles on an average of two or more times a year. With the increase in AIDS, the chance of such a health care provider being pricked by an AIDS contaminated needle over a period of years has become quite high. Further, other severe but less deadly diseases, such as hepatitis, are transmitted through contaminated needle pricks. Such pricks occur in many ways, such as a nurse tripping while carrying a used and exposed needle or even while trying to cap a used needle.
Consequently, a greater need has developed for shielding devices for needles of syringes such that the shielding devices are effective, easy to use and require only minor modifications to allow use with conventional types of disposable syringes. Numerous devices have been developed to reduce the risk of accidental needle pricks.
Many of these devices include a cylindrical sheath secured to the syringe which may be telescopically advanced and retracted to enclose and expose the needle of the syringe. The currently available shielding devices providing a cylindrical sheath to telescopically encircle the needle of a syringe suffer several shortcomings. Many of the existing devices require an operator to use both hands to position the protective sheath in encircling relation with the syringe needle thereby increasing the likelihood of accidental needle pricks. That is, when the user reaches with one hand to extend the sheath of the syringe being held by the other hand, the user accidentally sticks the free hand through carelessness, being bumped, or the like.
In many of the existing devices, the protective sheath cannot be locked in encircling relationship with the syringe needle possibly resulting in accidental needle pricks if a compressive force is inadvertently applied to the protective sheath. In other existing devices the protective sheath permanently locks in protective relationship with the syringe needle when advanced thereto preventing intermediate protection of the syringe needle where the syringe must be used more than once for a given procedure. Existing shielding devices also tend to require major modifications to existing syringes or greatly interfere with the normal use of the syringe.